Mt. Fuji May Be Close To Erupting

SpuriousLogic points out an article at Wired discussing research into pressure levels inside Mt. Fuji's magma chamber, which scientists claim is higher than it was in 1707, the last time it erupted. "The new readings, taken by the National Research Institute for Earth Science and Disaster Prevention, reveal that the pressure is at 1.6 megapascals, nearly 16 times the 0.1 megapascals it takes to trigger an eruption." A series of earthquakes shook the area around Mt. Fuji a little over a decade ago, and a fault line was discovered underneath it. "Since the March 2011 tsunami and the 6.4 magnitude earthquake that followed four days later, Japan has been on tenterhooks, and in May 2012 a professor from Ryukyu University warned that a massive eruption within three years would be likely because of several major factors: steam and gases are being emitted from the crater, water eruptions are occurring nearby, massive holes emitting hot natural gases are appearing in the vicinity." While the rising pressure within the magma chamber is of concern, it is but one factor among many that lead to eruptions.

Comments

Evacuation test run next year ???

[ACK!!]

From the article: "Regions that would be affected, including Kanagawa, Yamanashi and Shizuoka, plan to hold a test run of an evacuation by 2014, with a meeting of local governments covering progress of the plans and of shelter preparations slated for April 2013." It seems if the pressure is higher than the last time the damn mountain went boom that they would speed up preparations a tad. Wow, laid back disaster relief.

Re:"Nearly"?

[gman003]

Probably more than you think.

My high school had an Engineering Ethics class, mandatory for all students in a tech-related major. One of the case studies was the Pentium FDIV bug, and how Intel handled it. Other case studies included Tacoma Narrows, Chernobyl, and a bunch of other forgettable ones.

I graduated HS in '09. So "my generation" may be learning about it in a history class rather than through usage, but we *are* learning about it.

In other words, "no, YOU get off the lawn, old man!"

Re:Another thing to worry about...

[Rei]

I find it funny to hear all of the worry about things like Fuji. I mean, I know, I get it, it's roughly 100 km from Tokyo, which is a huge super mega-city. But living here in Iceland, hearing other places talking about "active" areas just seems kind of funny. I mean, the ground in parts of the capital region here in Reykjavík is just several hundred years old. On the hill right next to where I work, they drilled a 90 meter pipe into the ground, put a choke on the top, drip in water, and it erupts regularly as a geyser. A quarter of the city's hot water comes right from downtown. I mean, half an hour's drive (plus a bit of a walk) from my house you can walk *inside* a magma chamber. Not a lava tube, the actual magma chamber. It's empty now but there's other active magma chambers in the region.

And we're not considered one of the more active regions.

Fuji erupts every few hundred years, the biggest being VEI 5? Yawn. Katla's been threatening to go off any day now for the past couple years, and she's a VEI 6. And she's got an ice cap on top; last time she had a big eruption, she sent down a flood with as high a flow rate as the average outflow of the Amazon, Mississippi, Nile, and Yangtzee combined. That is, as much water flowing by as would fill up a cube over 200 feet on each side (roughly equivalent to a city block of 20-story buildings), every second.

Japan is volcanically active? As much as a third of the lava on Earth in the past 500 years is estimated to have come from Iceland.

Fuji's last big eruption was in the early 1700s? In the late 1700s we had Laki go off, most devastating eruption in recorded human history. A fissure opened up 23 kilometers long, up to 200 meters wide in places, with lava fountains as much as 1.5 kilometer in the air, erupting for 8 months straight. Sulfur dioxide was equivalent to a Mt. Pinatubo every three days. But that wasn't the worst, the worst was the anomalously high amounts of hydrofluoric acid. The eruption killed 80% of Iceland's sheep and even directly caused 23,000 human poisoning fatalities in the UK from the deadly blood-red cloud, as well as bizarre weather including tremendous thunderstorms with hailstones large enough to kill cattle.

So yeah, yeah, I know, Fuji is more of a threat because Japan has such huge coastal populations and economic activity and stuff, I fully understand that, but still... I guess your perception of risk is relative to your environment.